For more economical construction of warships, and to facilitate modernization, it is known from German publication No. DE PS 20 56 069 to furnish unit seating bases on the topside deck, on which weapons systems, fire control systems or navigational systems of known physical dimensions can be installed and interchanged when necessary as functional units. Because of such design, the functional unit systems can be constructed simultaneously with the construction of the ship's hull in a separate manufacturing operation, and subsequently installed on the individual unit support bases on the ship's deck. In this manner, practically no additional time may be required for the installation of the system in the ship. An additional advantage of such functional unit system lies in the fact that the functional unit installed in the ship can be removed at any time for maintenance or replacement purposes.
There are, however, nonstandardized devices, fixtures, systems and apparatus not only on the topside deck of a ship, but also at numerous locations in the interior of the ship on the lower decks. These devices, fixtures, systems and apparatus must likewise be easily transported into the ship and installed in such a way that they can be removed or interchanged easily. In prior art arrangements, however, for repair and maintenance work on the various systems, access ways had to be frequently made available over several decks, amounting to an enormous expense during the operational life of the ship. Retrofitting and/or modernization work which is required in such instances, often involves entire departments and sections, and the secondary costs incurred frequently exceed the cost of the actual retrofitted or modernized system several times over.